iowa state university - conceptual framework for …...2016/05/10 · 1 | p a g e conceptual...

| P a g e

Conceptual Framework

for an Iowa Pest Resistance

Management Plan

Resistance management is the effort to slow the development of pest adaptation to chemical,

genetic and agronomic control practices; foster methods of early, resistance detection; and

mitigate resistance as it arises.

State of Science Updates added: 5/10/2016

i| P a g e Conceptual Framework for an Iowa Pest Resistance Management Plan

CONTENTS Page

EXECUTIVE SUMMARY ................................................................................................... ii

1. INTRODUCTION AND BACKGROUND .................................................................... 1

2. PREPARING THE FRAMEWORK................................................................................ 2

3. IOWA PEST MANAGEMENT RESISTANCE PLAN PARTNERS ............................ 2

4. STATE OF THE SCIENCE............................................................................................. 3

4.1 Insect resistance ................................................................................................. 4

4.2 Weed resistance ................................................................................................. 6

4.3 Pathogen resistance ............................................................................................ 7

4.4 Sociologic considerations .................................................................................. 8

4.5 Economic considerations ................................................................................... 9

4.6 Regulatory considerations .................................................................................. 10

5. CRITICAL FEATURES OF AN IOWA PEST RESISTANCE

MANAGEMENT PLAN ................................................................................... 11

5.1 Holistic and long-term approach ........................................................................ 11

5.2 Framing and messaging ..................................................................................... 11

5.3 Incentives ........................................................................................................... 12

5.4 Agricultural financing and lease agreements ..................................................... 12

5.5 Individual- and community-based approaches for resistance management ...... 13

5.5.1 Defining communities ......................................................................... 13

5.5.2 Implementation drivers ....................................................................... 14

5.5.3 Tools for community leaders .............................................................. 15

5.6 Monitoring for results ........................................................................................ 15

5.7 Adaptive management approach ........................................................................ 17

5.8 Governance of a voluntary resistance management plan ................................... 17

6. RECOMMENDATIONS/CONSIDERATIONS FOR PLAN IMPLEMENTATION .... 17

REFERENCES ...................................................................................................................... 22

APPENDICES ....................................................................................................................... 25

Appendix A. Task Force and Contributors to the Conceptual Framework

Document ........................................................................................................... 25

Appendix B. January 30, 2015, Resistance Management Meeting

Recommendations for a State Resistance Management Plan ............................ 26

TABLES Proposed Logic Model for Coordination across Sectors .......................................................18

ii| P a g e Conceptual Framework for an Iowa Pest Resistance Management Plan

EXECUTIVE SUMMARY

Resistance management (RM) is the effort to slow the development of pest adaptation to

chemical, genetic and agronomic control practices; foster methods of early, resistance detection;

and mitigate resistance as it arises.

An outcome of a January 2015 meeting, entitled “Resistance Management: Whose Problem and

Whose Job,” included a call for developing a state-wide, voluntary, pest resistance management

(RM) plan. The meeting was attended by representatives from across Iowa’s agricultural

community. Subsequently, Iowa’s Agricultural Strategic Thinkers Acting Together Effectively

(Iowa AgState) concurred the time was right for preparing such a plan. A task force of

representatives, from a cross-section of Iowa AgState organizations, consortia of agricultural

pest management technology providers, the Iowa Department of Agriculture and Land

Stewardship (IDALS) and Iowa State University College of Agriculture and Life Sciences

(ISU/CALS), was formed to develop a conceptual framework for the plan. This paper, authored

by the task force, provides a framework that can serve as the foundation for developing an Iowa

RM plan during 2016.

Leaders and Partners

Successful implementation of the RM plan will require a “champion” and it is suggested the

Secretary or Deputy Secretary of IDALS serve in that role. The development and implementation

of a statewide, voluntary, RM plan ultimately requires strong leadership and partnerships from

Iowa’s farmer, commodity, agricultural retailer, crop adviser, and crop consultant organizations

and pest management technology providers, in association with IDALS and ISU/CALS. The RM

plan could be coordinated by IDALS, which would also be responsible for apprising the

Environmental Protection Agency and the United States Department of Agriculture of the plan

and its implementation. ISU/CALS would continue to develop and compile the science on pest

resistance and RM strategies, including economic implications, and could be the hub for

developing outreach materials for the agriculture community.

State of the Science to Support RM

Common themes concerning resistance development and management in insects, weeds and

pathogens are evident; however, specific details vary across pests and pest management

practices. Resistance management practices should include a diverse combination of crop

rotations, effective use of different pesticide modes of action, seed with stacked native and

biotechnology-derived traits, and mechanical controls in the context of diligent use of integrated

pest management (IPM). IPM includes scouting to assess pest pressure and monitoring for early

detection of poorly performing pest management technologies. Employing these RM practices

are likely to increase input costs, time commitments and production complexity in the near term,

but long-term productivity and profitability will likely be higher due to the reduced rate of pest

resistance development.

iii| P a g e Conceptual Framework for an Iowa Pest Resistance Management Plan

Research surveys show that Iowa farmers and agricultural stakeholders are aware that pest

resistance is a problem, and they are concerned. They also share the belief that multiple

stakeholders bear responsibility for RM and proactively taking action. The surveys suggest there

is common ground on which to build coordinated approaches to RM.

To facilitate the development of an Iowa RM plan, knowledge and understanding of current and

potential science, technology and production agriculture management solutions as well as

applied socioeconomic analyses of different pest resistance problems and RM practices is

needed. These analyses will help to better understand current RM options and the perceived and

actual costs, and short- and long-term benefits of RM practices, as well as reveal which RM

practices provide the most significant return on investment.

Critical Features of a Plan

The nature of pest RM requires a plan that incorporates a long-term, integrated approach to pest

management, and its costs and benefits. The goal of the plan is to document and promote holistic

and integrated management solutions that will effectively and sustainably control pests, and

postpone or delay resistance development, foster methods of early detection, and then mitigate,

to the extent possible, the spread of pest resistance. Framing and messaging the plan and its goal

of promoting R&D investments and extending the long-term viability of effective pest

management technologies will be critical. Other key elements of the plan will likely need to

address education and outreach, incentives, financing and lease agreements, monitoring

implementation and results, and governance.

Ultimately, the actions of individuals will be the key facet of the Iowa RM plan, but achieving

the desired outcomes of these actions may require community-based approaches. The proposed

framework suggests some options for defining communities, discusses the need for leaders

within communities and stresses the importance of coordinated efforts of all stakeholders.

Recommendations and Considerations for Implementation

Development and implementation of the Iowa plan would be facilitated by IDALS and

ISU/CALS. Critical to implementation of a state RM plan is long-term engagement of the Iowa

agricultural community and allied industries. The paper proposes a framework that links

production decisions and pest management strategies and costs with human behaviors, including

land owners’, farm operators’ and agriculture financing entities’ decisions and investment

strategies for land-management practices, and delayed development of pest resistance. The roles

for each sector of Iowa agriculture within this framework are outlined. Plan implementation will

be based on an evolving state of the science and will leverage existing partnerships, networks

and roles within Iowa communities. The Iowa plan should facilitate recognition of individuals,

leaders and ‘champions’ who emerge.

1 | P a g e

Conceptual Framework for an Iowa Pest Resistance Management Plan

December 18, 2015

1. INTRODUCTION AND BACKGROUND

January 30, 2015, State-wide Meeting:

The impacts of pest adaptation to chemical, genetic and agronomic control practices concern

many sectors of the agricultural community. Due to growing concerns and the changing national

regulatory framework to address pest resistance management (RM), Iowa State University,

College of Agriculture and Life Sciences (ISU/CALS) and the Iowa Department of Agriculture

and Land Stewardship (IDALS) facilitated a one-day meeting on January 30, 2015, to discuss

RM options in Iowa crop systems. The meeting included representatives from the Iowa

community of farmers, agriculture support networks, and pesticide and biotechnology

companies. Planning for the workshop included input from Iowa farm organizations,

cooperatives, agricultural retailers, certified crop advisers, independent crop advisers, land

management firms, and pesticide and biotechnology companies. The meeting summary report

can be accessed at: http://www.ipm.iastate.edu/content/pesticide-resistance-workshop-2015.

The major recommendations from the meeting included:

Developing a statewide, voluntary, RM plan coordinated by the State that includes broad

participation from all sectors of Iowa agriculture

Establishing a unified, consistent message to increase awareness for action

Sharing of meeting outcomes by each meeting participant within their organization

Meeting participants concluded that developing an Iowa RM plan was a high priority. It was

suggested that development and implementation of a plan be facilitated by the state (perhaps in a

manner similar to the Iowa Nutrient Reduction Strategy) and bring together broad participation

across the agricultural community. It was noted that development and implementation of such a

plan would require strong leadership from Iowa’s farm owners and operators, commodity,

agriculture retailer, crop adviser, and crop consultant organizations, and pest management

technology providers, in association with the State and ISU/CALS. It was further noted that a

plan, with clearly defined objectives and roles across all sectors in agriculture and flexibility for

different parts of the state, could minimize the potential for regulatory intervention.

Meeting participants also discussed some initial perspectives on the tactical aspects of

implementing an Iowa RM strategy. For example, it was deemed critical to include socio-

economic analyses to inform problem definition and potential solutions. Identifying potential

funding options for developing and implementing the plan, and establishing effective means to

deliver information and tools to individuals and communities were also emphasized.

While building a coalition of organizations to work with Iowa to develop an RM strategy may

take some time, meeting participants indicated that increasing awareness of the need to take

action could be addressed immediately. In this regard, the need to develop and deliver a unified

http://www.ipm.iastate.edu/content/pesticide-resistance-workshop-2015

2| P a g e Conceptual Framework for an Iowa Pest Resistance Management Plan

message and increase outreach to farm owners, including absentee land owners, and operators,

especially short- and long-term renters, and their advisers was stressed.

Finally, the participants noted that it was essential that they take back to their organizations the

messages from the day’s meeting. This was viewed by several participants as the key immediate

next step to help increase awareness of the issue and for organizations across Iowa to explore the

potential development of a State RM strategy.

June 19, 2015, AgState Meeting:

On June 19, 2015, ISU/CALS and IDALS met with Iowa’s Agricultural Strategic Thinkers

Acting Together Effectively (Iowa AgState) to discuss the January 30th meeting

recommendations. At the June meeting it was agreed that a task force be formed to prepare a

conceptual framework for an Iowa pest RM plan and report back to AgState and leadership of

related organizations in December 2015. Assuming agreement on the conceptual framework,

with modifications as recommended, the plan itself would be developed during 2016.

Task Force:

The task force was formed in September 2015, with representatives from the Agribusiness

Association of Iowa, Agricultural Biotechnology Stewardship Technical Committee, Iowa Corn

Growers Association, Iowa Chapter of the Society of Farm Managers and Rural Appraisers,

Iowa Farm Bureau Federation, Iowa Institute for Cooperatives, Iowa Soybean Association,

Resistance Action Committees, and Practical Farmers of Iowa. The task force efforts were

facilitated by representatives from ISU/CALS and IDALS/Pesticide Bureau. Contributors to this

framework document are listed in Appendix A.

2. PREPARING THE FRAMEWORK

The task force met by teleconference and in person during September, October and December,

2015. Task force deliberations involved a review and discussion of the January 30, 2015,

meeting summary (see Appendix B) and relevant scientific literature (see REFERENCES).

The task force prepared the proposed conceptual framework through written contributions of

individual members and group discussions. The framework represents a consensus of the task

force; however, in some instances the group noted where different options or approaches should

be considered as the conceptual framework evolves into a state plan.

3. IOWA PEST RESISTANCE MANAGEMENT PLAN PARTNERS

The development and implementation of an Iowa RM plan requires strong leadership from

Iowa’s land owners, farmer, commodity, agriculture retailer, crop adviser and crop consultant

organizations, and pest management technology providers, in association with the IDALS and

ISU/CALS. Specific recommendations for different sectors within the agricultural community

are anticipated, e.g., crop protection companies and retailers may be encouraged to create

internal incentives for promoting RM, provide common/consistent messaging and advice, and

ensure sufficient supply of products are available that support diverse modes of action and/or

crop rotations; farmers may be asked to participate in demonstrations, provide data and feedback


on feasibility of practices, and lead and promote peer-to-peer discussions on the issue; and

ISU/CALS should be relied upon to continue to develop and compile data on resistance and RM

practices, including economic feasibility, and be the hub for identifying and developing outreach

materials the agricultural community can employ.

The management plan, with clearly defined roles across all sectors in agriculture, would need to

be coordinated by IDALS. In turn, IDALS would be responsible for apprising the Environmental

Protection Agency (EPA) and the United States Department of Agriculture (USDA) of the plan

and its implementation to minimize the potential for regulatory intervention.

In summary, all of the following will have important roles to play in the successful

implementation of an effective RM plan in Iowa:

Iowa agricultural organizations

Row-crop farmers, including land/farm owners and farm operators/renters

Independent and certified crop advisers

Seed, crop protection, technology/service, fertilizer providers, ag retailers

Land owners, land managers

Urban and rural community members

EPA and USDA

4. STATE OF THE SCIENCE

In preparation for the January 30, 2015, meeting, background papers (http://bit.do/state-of-the-

science) were developed that addressed the state of the science concerning western corn

rootworm resistance to Bt traits, weed resistance to herbicides, and pathogen resistance to

genetics and fungicides in Iowa and surrounding states. The background documents also

included a summary of socio-economic issues.

A brief synopsis of these background papers, updated as appropriate, is provided below. Several

common themes concerning resistance development and management in insects, weeds and

pathogens are evident; however specific details vary across pests and pest management practices.

For example, less complicated pest management technologies reduce time and costs, but if the

same technology is used over multiple seasons, the likelihood of resistance development

increases. With resistance development there can be increasing costs and complexity for pest

management and reduced productivity over time.

RM practices include, but are not limited to, crop rotations, technology diversity, mechanical

control methods, and diligent use of integrated pest management (IPM), including scouting for

pest pressure and early detection of resistance by observing poor performance of targeted-pest

management. For RM efforts to be effective the appropriate suite of practices needs to be

employed. While employing RM practices increases input costs in the near term, long-term

productivity and profitability will likely be higher due to the reduced likelihood of resistance

development and its associated costs of pest management and/or reduced yields.

There can be situations where RM can be relatively simple, straightforward and successful when

practices employed by individual farmers are not influenced by practices employed by their

http://bit.do/state-of-the-science

http://bit.do/state-of-the-science


neighbors – typically in situations where resistant pests are immobile and do not infest

neighboring farm fields. In cases where a resistant pest is mobile and it can infest neighboring

farmers’ fields, the coordinated RM practices by farmers can help ensure that all in the

community will benefit from the longer-term productivity and profitability associated with

delayed evolution of pesticide resistance.

4.1 Insect resistance

Insect pests have repeatedly demonstrated an ability to evolve resistance to insecticides,

including insecticidal proteins derived from the bacterium Bacillus thuringiensis (Bt), which are

used in genetically modified crops. Western corn rootworm is among the most serious pests of

corn in North America, and Bt corn is currently used to manage this pest (Gray et al. 2009). The

first commercially available Bt hybrids for management of rootworm were grown in 2003 and

produced Bt toxin Cry3Bb1. Beginning in 2009, severe feeding injury to single-trait Cry3Bb1

corn was observed in Iowa, and subsequent bioassays revealed that this feeding injury was

associated with Bt resistance (Gassmann et al. 2011). These fields, with Cry3Bb1-resistant

western corn rootworm, had a history of continuous corn cultivation and three or more years in

which Cry3Bb1 corn was grown. Additionally, these fields were associated with feeding injury

to Bt corn of greater than one node of root injury, which translates to an average yield reduction

of 17 percent (Dun 2010). In 2011, cases in Iowa of severe feeding injury to Bt corn by western

corn rootworm expanded to include mCry3A

corn. Subsequent bioassays found resistance

to both mCry3A corn and Cry3Bb1 corn, and

cross-resistance between these Bt toxins

(Gassmann et al. 2014).

Adult western corn rootworm exhibit limited

dispersal, traveling less than 40 meters per day; however, longer-distance dispersal also occurs.

This limited adult dispersal facilitates resistance evolution if a farmer uses the same management

tactic continuously, because adult female rootworm tend to oviposit eggs into the same field

from which they emerged, completing their entire life cycle in a single field. Initially, resistance

is expected to exist in a patchwork among fields, occurring in fields where the same management

practices have been used repeatedly (Gassmann et al. 2011). Over time, however, the movement

of Bt-resistant adults across the landscape can lead to the presence of Bt-resistant western corn

rootworm, and substantial feeding injury to Bt corn, in fields without a history of continuous use

of the same Bt trait and continuous corn cultivation (Gassmann et al. 2014). As a result, although

an individual farmer may bear the immediate costs when a population of Bt-resistant western

corn rootworm evolves, there is the potential for resistance problems to expand and affect

farmers in the broader landscape if appropriate actions are not taken.

In addition to cases of Bt resistance by western corn rootworm, this pest has also developed

resistance to crop rotation in Illinois, by ovipositing outside of cornfields, and resistance to adult

management with pyrethroids in Nebraska and Kansas (Spencer and Levine 2008, Pereira et al.

2015). In Iowa, northern corn rootworm displays resistance to crop rotation though extended

diapause, overwintering in the soil for multiple years (Krysan et al. 1986). Although, historically

Resistance management is the effort to slow the development of pest adaptation to chemical, genetic and agronomic control practices.


found in northwestern Iowa, rotation-resistant northern corn rootworm now extends into the

eastern half of Iowa (Dunbar and Gassmann 2013).

In contrast to western corn rootworm, European corn borer has been managed successfully with

Bt corn since the 1990s, with no documented cases of Bt resistance in Iowa or elsewhere in the

United States (Siegfried and Hellmich 2012). The greater mobility of adult European corn borer

compared to western corn rootworm, and, consequently, greater mixing of populations from

refuges and Bt fields, is likely an important factor contributing to this effect. Additionally, Bt

toxins targeting European corn borer are high dose, killing both susceptible individuals and

individuals that are heterozygous for resistance. Finally, pyramided Bt corn targeting European

corn borer was brought to the market before any cases of resistance occurred, which has

probably helped to maintain Bt susceptibility in this pest.

Resistance to conventional insecticides by soybean aphid has yet to be documented in Iowa.

However, extensive reliance on conventional methods to manage this pest, including

neonicotinoid seed treatments and several classes of foliar insecticides, are placing intense

selective pressure on this pest to develop resistance (Ragsdale et al. 2011). Recent control

failures of foliar insecticide treatments in southwestern Minnesota may be a harbinger of

insecticide resistance developing, although more research is required to determine whether

resistance is present (Koch et al. 2014). Additionally, there are now biotypes of soybean aphid

that have adapted to host-plant resistance in soybean (Ragsdale et al. 2011).

Other pests of relevance to soybean production in Iowa include two-spotted spider mite and bean

leaf beetle. Two-spotted spider mite, although primarily a problem in soybeans during dry years,

is a pest that has repeatedly demonstrated an ability to evolve resistance, with documented

resistance to more active ingredients than any other arthropod (Van Leeuwen et al. 2010).

Insecticide resistance by bean leaf beetle has not been documented in Iowa, although reduced

susceptibility to pyrethroids has been found for some regions of the southern US (Musser et al.

2012).

Cases of resistance by western corn rootworm to Bt corn and crop rotation, and resistance to

conventional insecticides by many pest species, illustrate the potential for insects to adapt to

management practices by developing resistance. To delay the evolution of Bt resistance by

western corn rootworm, farmers should plant non-Bt refuges and apply IPM by rotating among a

variety of tactics, including crop rotation, Bt traits and soil-applied insecticides. Crop rotation is

an effective IPM tool for western corn rootworm because rootworm larvae cannot survive on

soybean roots, and as a result, rotating fields out of corn production breaks the lifecycle of

western corn rootworm and is highly effective at reducing pest abundance. Because of resistance

to Cry3Bb1 corn and mCry3A corn by western corn rootworm in Iowa, it is advisable for

farmers to use corn pyramided with Cry34/35Ab1 and either Cry3Bb1 or mCry3A. By applying

a diversity of management tactics, selection for resistance to any single tactic will be reduced and

the evolution of resistance delayed.

In general, farmers can slow the development of resistance by insects through a diversified

management approach and the judicious use of insecticides.


4.2 Weed resistance

The scientific literature is replete with papers on herbicide resistance in weeds. Research

describing evolved resistance to herbicides represents the major component of the weed science

effort nationally and internationally. Areas of interest include the specific mechanisms by which

weeds evolve resistance to herbicides, the implications of multiple resistances, the genetics of

herbicide resistance, and the impact of herbicide resistance on weed fitness.

A project sponsored by the Iowa Soybean Association (Owen et al. 2015) to assess herbicide

resistance in Iowa has provided a clear picture of existing resistances in waterhemp,

marestail/horseweed and giant ragweed. A high percentage of Iowa fields have herbicide-

resistant waterhemp, with a majority of the populations demonstrating multiple resistances. The

most common multiple resistances in waterhemp is to Herbicide Group (HG) 2 (ALS inhibitor

herbicides), 5 (PSII inhibitor herbicides), and 9 (EPSPS inhibitor herbicides). A small percentage

of waterhemp populations have resistance to 5 herbicide groups. Evolved resistance in

waterhemp to HG 14 (PPO inhibitor herbicides) and 27 (HPPD inhibitor herbicides) is increasing

rapidly. Recently, resistance to HG 4 (auxin herbicides) has been reported in Illinois and

Missouri waterhemp populations. Clearly HG 4 resistance as well as resistance to HG 14 and

HG 27 are serious threats in Iowa.

All of the weeds in Iowa with evolved resistance to herbicides are annual and are well adapted to

current production agriculture systems. Once established in a weed population, the resistance

remains despite the fact that the HG in

question has not been used recently. Herbicide

resistance in all HGs is likely nuclear and the

trait(s) that codes for herbicide resistance is

dominant or semi-dominant. In the current

Iowa crop production system, the risk of

herbicide resistance is generally high and will soon become a serious, widely distributed problem

in most Iowa fields. A number of predictive models have been developed to assess the evolution

of herbicide resistance in a number of weed species. However, they have not been widely applied

in weed management decisions. A significant economic impact is expected, but this is difficult to

estimate, as are social impacts in cases where resistant weeds are mobile and can move into

neighboring farmers’ fields. Strategies for driving broader application of predictive modeling and

similar tools will be presented later in this document.

In a general sense, weed management has not changed greatly over the last six decades. Current

strategies include chemical-based approaches (often used due to cost and convenience), cultural,

mechanical and, to a lesser degree, biological. The emphasis has been on chemical strategies and,

given the unprecedented adoption of genetically engineered crops with tolerance to glyphosate,

biotechnology traits, and chemistry combinations, almost to the exclusion of mechanical and

cultural strategies. Options to address the burgeoning problem of evolved resistance to herbicides

It is increasingly understood that evolution of resistant pests is both a biological and social problem.


are understood but poorly accepted by Iowa farmers. One key to managing herbicide resistance

is to diversify weed management practices beyond using herbicides.

4.3 Pathogen resistance

Like insects and weeds, plant pathogen populations can evolve due to selection pressure from

pesticides or crop resistance. How quickly this shift occurs depends on the genetics of the

pathogen and the choice and use of the pesticide or crop variety. There are numerous examples

in the literature of pathogens evolving resistance to fungicides within a couple of growing

seasons. For example, the cereal powdery mildew or, closer to home, the frogeye leaf

spot fungus, are resistant to strobilurin fungicides. There are very few choices of fungicides

available to farmers. Similarly, there are a limited number of sources of host plant resistance for

fungal pathogens and soybean cyst nematode (SCN).

When pathogen resistance develops, it is usually not as obvious as with Bt-resistance, where

lodged corn is evident; or herbicide resistance, where weeds are easily visible growing over the

intended crops. Damage from many pathogens is generally more subtle and sporadic. Crops may

be less vigorous, stunted or deformed, discolored, senesce earlier, or just have lower yields.

The sources of resistance for SCN include: PI88788, Peking and PI 437654 (Tylka and Mullaney

2015). It is important to note that 97 percent of commercially available soybean varieties use

PI88788. Repeated use of soybean varieties with the same source of resistance can result in SCN

populations developing increased levels of reproduction on that source of resistance. There is

evidence of this happening with PI88788 resistance in Iowa. Therefore, soybean varieties with

resistance from different sources should be grown to slow the evolution of SCN resistance to

soybeans with PI88788. In addition, there are chemical and biological options, as well as some

cultural practices, which farmers can consider as components of a RM strategy and as

components of an integrated approach to managing SCN and other nematode problems.

The most common foliar fungicides currently registered for use in Iowa include only a few

classes of fungicides: strobilurin (FRAC Code 11), triazoles (FRAC Code 3), and SDHI (FRAC

Code 7) fungicides. The FRAC Code of a product is based on the mode of action of the

fungicide. To reduce the risk of fungicide resistance developing, fungicides belonging to

different FRAC codes should be used in an integrated or rotating fashion to manage crop disease.

Many of the commercial products combine two or more fungicide classes (FRAC codes).

Seed treatment fungicides include the same classes as the foliar fungicides, but also include a

few additional classes such as: phenylamides (FRAC Code 4), thiazole carboxamide (FRAC

Code 22), phenylpyrrols (FRAC Code 12), and methyl benzimidazole carbamates (FRAC Code

1).

To reduce selection for fungicide resistance, farmers should use products in combination with

other disease management practices such as disease resistant varieties, rotation and other cultural


practices, such as varied tillage, planting dates, plant populations and row spacing. Moreover, a

fungicide should be applied only when needed, early in disease development, and at full label

recommended rates. Some fungicide-use advisers have emphasized that broad prophylactic

application of fungicides can promote overall plant vigor and increased yields. Farmers should

be cautious of this practice, as it may contribute to more rapid fungicide resistance development.

Monitoring for pathogens or specifically for certain strains of pathogens that are insensitive to

the targeted management (variety or fungicide) is often time consuming and requires trained

personnel. However, farmers and agronomists can monitor and address selection for pest

resistance by scouting for disease after a fungicide application is made. If the disease does not

appear to be controlled by the fungicide, it should be investigated.

Fungicide resistance has been reported in numerous disease-causing pathogens of crops

including frogeye leaf spot of soybean. The pathogen that causes frogeye leaf spot is genetically

diverse, and strains have been found in the Midwest that are insensitive to strobilurin fungicides.

This disease is consequently a model system for developing an RM-monitoring plan.

4.4 Sociological considerations

It is increasingly understood that evolution of resistant pests is both a biological and social

problem. Dealing with resistance will require substantial changes in management strategies.

Failure to act in the short term will likely lead to much greater costs in the long term (Jussaume

and Ervin 2014). Behavioral responses to problematic situations, however, depend in large part

on beliefs about whether a problem exists and the degree to which it poses risks (Nigg and Mileti

2002). In other words, people change their behaviors only if they believe that (1) a problem

exists and (2) that it represents a threat.

Accordingly, a first step toward addressing the problem of resistant pests is the development of

an understanding of beliefs and perceived risks by farmers and stakeholders. Survey research in

Iowa in 2012 and 2013 documented that 82 percent of farmers agreed that they were concerned

about herbicide-resistant weeds becoming a problem and 62 percent were concerned about Bt-

resistant insects becoming a problem in the areas where they farm (Arbuckle 2014). Importantly,

very few farmers were confident that new technologies would be developed to help manage

resistant pest populations. Further, farmers surveyed also understood that the way pest-

management technologies are used has a major impact on the rate of resistance evolution, and

they viewed RM as a community problem involving multiple stakeholders (e.g., farmers and the

private and public sectors).

Similar (though less methodologically rigorous) surveys of representatives from three Iowa

stakeholder groups—agricultural retailers and advisers, farmer and commodity associations, and

pesticide/biotechnology companies—indicated that these stakeholders are also highly aware of

and concerned about pest resistance. Results from a non-random sample of representatives from

these stakeholder groups showed that they are concerned about pest resistance; believe that

farmers’ actions play a major role in the evolution of resistance; understand that farmers look

first to agricultural retailers for information to help them make pest management decisions; and

believe that multiple stakeholders, including farmers, private firms, and public universities and

agencies bear responsibility for RM.


In short, survey results showed that Iowa

farmers and agricultural stakeholders have

similar perspectives on pest resistance and

RM. They believed that resistant pests are a

problem, and they are concerned. They also

share the belief that multiple stakeholders bear

responsibility for action. Taken as a whole,

these survey results suggest there is much

common ground on which to build coordinated approaches to RM.

4.5 Economic considerations

All pest management and RM decisions have long-term socioeconomic implications that need to

be better understood across the agricultural sector. Most decisions involving variable production

inputs are made on an annual or short-term basis. Research is needed to determine to what extent

the returns outweigh the costs. It has become more evident that the economics of pest

management need to be treated as a long-term decision. Initially, pest management efficacy or

“killing effectiveness” is a fixed stock like any nonrenewable natural resource. Efficacy can be

depleted or exhausted through resistance development by overuse of a pest management

technology. Only with judicious use of a combination of RM practices can the efficacy (or

economic value) of pest control practices be sustained over the long-term. Once resistance

evolves and efficacy is depleted, susceptibility cannot be restored or renewed for a particular pest

control chemical or trait. The only alternative at this point is to develop a new product or trait or

better, to use a combination of RM practices to achieve a degree of pest control, albeit at a higher

cost. Included in the long-term socioeconomic implications should be spillover of resistant pests

into neighboring farms that are external to the individual farmer’s pest management cost

decisions, but impose a social cost, and possibly a financial cost, to their neighbors. RM

practices have to be built on goals of maximizing long-term net benefits to both the farmer and

neighboring farmers and improving long-term net benefits to the farm community (Miranowski

and Carlson 1986).

To facilitate the development of an Iowa RM plan, applied socioeconomic analyses of different

pest resistance problems and RM practices are needed. These analyses will help to better

understand the perceived and actual spillover costs, and short- and long-term benefits and costs

of RM practices, as well as reveal which RM practices provide the most significant return on

investment. For example, Miranowski and Lacy (2015), Livingston et al. (2015), and Arbuckle

(2014) help shed light on this issue.

A community-based RM approach will yield greater benefits when a farmer’s pest management

practices lead to spillovers on neighboring farmers and members of the community. For a

spillover, the pest has to be relatively mobile and the resistance problem has to be transferred

with the mobile pest. If seeds from a resistant weed travel from a farmer’s field to a neighbor’s

field, the neighbor may incur significant costs if unable to control the weed. Alternatively, if a

farmer’s Bt-resistant western corn rootworm beetles travel to the neighbor’s field, the neighbor

may be able to manage the pest if using a crop rotation that breaks the cycle. The first case may

While employing RM practices increases input costs in the near term, long-term productivity and profitability will likely be higher due to the reduced likelihood of resistance development.


realize significant community benefits from intervention. The second case may only cause

significant root injury to a neighbor’s field the following year if the neighboring farmer is

planting continuous corn. The western corn rootworm spillover is more likely in areas with a

prevalence of continuous corn and use of the same Bt trait (Gassmann et al. 2011).

It is important to point out that the initial adoption of RM practices may improve long-term net

benefits but reduce short-term net benefits. Both individual farmers and neighboring farmers in

the community will be better off in the long term with RM practices. At the same time, even

though longer-term net benefits may be improved by RM practices, it does not ensure that all

farmers will adopt RM practices. Some may even sacrifice short-term benefits for simplicity,

time-savings, convenience, and other behavioral reasons. Commodity prices, yield risk, and

uncertainty may further drive the short-term focus. Subsidized crop insurance is designed to

offset short-term price and yield uncertainty, but it may actually cause some farmers to focus

more on short-term net benefits and discourage adoption of RM practices (unless they are a

condition of receiving indemnity payments). A community-based approach needs to recognize

these challenges as well as farmers’ willingness to cooperate to control pests (Stallman and

James 2015) when considering options for addressing them as a community.

4.6 Regulatory and policy considerations

EPA and state pesticide agencies have a potential regulatory role to address resistance

development and management under the Federal Insecticide, Fungicide, and Rodenticide Act

(FIFRA). At both the state and federal level there is increasing attention to RM. The extent to

which current regulatory approaches are effective and the extent to which adjustments may be

needed in terms of education and/or increased regulatory requirements are being evaluated.

There is a general sense that regulatory agencies will continue to support enhanced education and

training.

For conventional pesticides, federal pesticide labels approved by EPA often include advisory

language regarding RM. Combined with state pesticide applicator training and pesticide

stewardship training, this advisory language has generally been the extent of regulatory oversight

to date. For Plant Incorporated Protectants (e.g., Bt), EPA has required RM practices (e.g.,

refuges) through conditions of registration. EPA is currently asking public comment on greater

specificity to management requirements for Bt corn traits. For herbicides registered for use with

herbicide tolerant crops, EPA is initiating an approach to implement RM practices through

enforceable or advisory language on Federal labels and through conditions of registration placed

on the herbicide registrants.

Through the Plant Protection Act, USDA’s Animal and Plant Health Inspection Service must

determine if traits imparting herbicide tolerance or resistance can be deregulated. As part of this

decision, USDA undertakes an environmental assessment under the National Environmental

Protection Act (NEPA) for all proposed de-regulations. To date, the USDA decisions have

included an assessment of herbicide resistance development and management within the NEPA

analyses; however, since EPA, under FIFRA, is responsible for determining conditions under

which herbicides may be registered, USDA has determined it does not have regulatory authority


to directly address RM practices in its deregulation decisions. Consequently, USDA’s role in RM

is generally one of advancing research, incentives and outreach to promote RM practices.

The expansion of subsidized crop insurance under the 2014 Farm Bill safety-net legislation may

be creating a potential disincentive for adoption of RM practices, unless RM practices are

required to receive indemnity payments for crop losses (Miranowski, Ernst and Cummings

1974). If the deductible portion of the yield loss is small, it may create a disincentive to adopt

more costly RM practices in controlling or managing pests. Unfortunately, no research studies

have yet looked at the potential impacts of expanded use of subsidized crop insurance on RM.

5. CRITICAL FEATURES OF AN IOWA PEST RESISTANCE MANAGEMENT PLAN

5.1 Holistic and long-term approach

The nature of RM requires the Iowa RM plan

to incorporate a long-term, holistic approach

to pest management. It could begin with a

clear overview of current issues and realistic

future threats and timeline, followed by

embedding the importance and essentials of RM into the broader topic of IPM. Key concepts

include challenges due to a lack of IPM in row-crop agriculture, the need for a more holistic and

ecosystems approach to pest management, and the need to move from a short-term to a long-term

and more community-focused approach when making farm management decisions. Plan

management should complement other sustainability plans, such as preventing soil erosion,

preserving water quality, enhancing pollinator and wildlife habitat, and managing nutrients

(Nutrient Reduction Strategy), to the extent possible. There may be instances where some

recommended RM practices (e.g., tillage) and other conservation practices (conservation tillage)

may need to be modified to best optimize attainment of multiple sustainability objectives.

5.2 Framing and messaging

Once RM issues and risks are clearly described, the plan needs to plainly state that the

development of resistance does not indicate a failure of the RM plan. When a RM plan is

implemented, it will not necessarily prevent resistance. The goal of the plan is to postpone or

delay resistance, foster methods of early detection, and then mitigate resistance as it arises.

The RM plan also needs to anticipate new technologies, even if these new technologies appear to

be strong RM candidates. The plan needs to emphasize that IPM and RM dovetail together and

form the core of the plan, both for current and future technologies.

Key elements of the plan are a common message and a state champion. A champion for this plan

might be the Secretary or Deputy Secretary of IDALS. Iowa State University and IDALS will

provide guidance on RM to the implementation drivers.

The nature of RM requires the Iowa plan to incorporate a long-term, holistic approach to pest management.


5.3 Incentives

Helping land owners, especially absentee land owners, and farm operators, especially short-term

lessees, understand the rationale and importance of investing in short- and long-term RM

strategies is a critical first step to a successful RM plan. Promoting or incentivizing long-term

sustainable pest management approaches for people and organizations will be critical. Existing

or new USDA programs could play a role in this regard. Perhaps USDA’s Natural Resource

Conservation Service and/or the Farm Service Agency EQIP and CRP programs could be

structured to help defray input costs associated with RM practices. In addition, USDA’s crop

insurance policies could be re-evaluated to help support RM. The plan could explore ways to

incentivize pest management technology through USDA by a pest management credit and the

possibility of selling the credits.

The plan could address what happens to sustainability of a pest management technology if there

are no incentives or when incentives go away. There will be a need to avoid the pitfall of the

nutrient reduction strategy where people held off on participation until incentives were in place.

It will be important to recognize people who are currently using sound RM strategies. It will be

necessary to provide incentives not only for people establishing new RM practices, but also for

those who have already been employing sound RM approaches. RM must be an on-going effort,

not a one-time cost share that has worked for some programs. Transparency for participants in

the plan may be helpful to foster wider participation.

5.4 Agricultural financing and lease agreements

Another critical piece of the plan is financing. Currently, operating loans may include only a

small amount of money for pest management. For example, $20 per acre for an herbicide

program may not allow for a sound RM plan. Changes in how operating budgets are financed

and negotiated could also take a long-term view. The state RM plan needs to communicate the

central idea of investing more now to ensure an economically-viable future. This may entail an

educational program that includes stakeholders and influencers and extends to land managers,

landlords/land owners, bankers, loan officers, and attorneys who draft rental agreements, who are

all within the suggested “community” (see Defining Communities below).

Committing to a sustainable and holistic approach creates a challenge to build the importance

and essentials of RM into the broader topic of pest management, along with all other

considerations, operations and players that have a role in agriculture production, i.e. farmers,

land owners, Certified Crop Advisers (CCAs), independent crop advisers, cooperatives,

applicators and companies. Everyone needs to begin, if they have not already, thinking of

managing/delaying pest resistance as part of their overall strategy and operations for pest

management. These ideas also potentially extend to land managers, lawyers and land

management companies. How do farm managers reward good RM practices? How do we address

the potential problems that arise with cash rent? Should land managers require RM as part of a

lease agreement, for example, by documenting use of multiple modes of pesticide action by

renters?


Because the RM plan will emphasize the need to move from a short-term approach to a long-

term approach, a standard “sustainability clause” could be added to all financially-related

agreements for growers. It could be a consideration for each agreement to make funding or future

rights-of-rental dependent on appropriate management of the land (soil, water, nutrients, and

pests). Any element, like weed or rootworm resistance, could devalue the land and should

potentially be considered. There are examples of such land devaluation in other cropping

systems, e.g., resistant ryegrass in Australian wheat. Regardless, standard rental agreements may

need to be revised to incorporate RM. There is a standard form that is used by attorneys when

land is rented. This default form needs to be updated to include recommendations regarding RM.

At the very least, farm owners and operators should be made aware of how pest resistance affects

yield and value of grain (e.g., quality, docking, test weight). It may be incorrectly assumed that

most farmers have a high degree of flexibility

to influence these desired changes. Due to

operating loan restrictions, land rental

agreements, local farm competition, or loyalty

to specific traits or chemistry providers,

farmers may base their decision more on these

external influencing factors than on considerations about specific pests or sustainability.

5.5 Individual- and community-based approaches for RM

The actions of individuals will be key components of an RM plan, but achieving the desired

outcomes of these actions will require community-based approaches. There may be incentives

for good RM but key inhibitors are the potential near-term input costs to individuals and

communities. Incentives to good RM may include concern of additional regulation, but more

importantly, the development of resistance means that farmers will lose efficacious technologies

and pest management costs likely will increase. Although individual farmers where resistance

first arises will most likely experience the most severe financial effects, neighbors also will

experience problems due to pest movement. As a result, there are incentives to approach RM at

the community level and the individual level. Consideration should also be given to state border

communities where adjacent farms across state lines may not be part of the plan, discouraging

adjacent Iowa communities from participation.

5.5.1 Defining communities

The community’s size and the associated management recommendation should reflect the

nature of the pest, resistance attributes, and the size and scope of the risk. The size and

composition of the community could be small or large depending on the pest, the current

situation, the stakeholders, and the potential risk.

Weeds are ubiquitous and resistance is widely spread across the state. Thus, the “size” of

a community could be relatively small or large compared to other pest complexes.

Communities based on weed species may work for giant ragweed and Palmer amaranth,

but the ubiquitous distribution of waterhemp, and to a lesser degree marestail/horseweed,

The state RM plan needs to communicate the central idea of investing more now to ensure an economically viable future.


make community size more a factor of smaller scale. For marestail/horseweed the

community designation could be the tillage system.

Western corn rootworm resistance is spreading but currently somewhat localized and

some opportunity exists to provide a supportable and logical recommendation for

community size.

Diseases can be transient, sporadic and resistance to fungicides and nematicides has yet

to be described in Iowa, however, SCN has developed resistance to some host-plant

varieties. A statewide community for SCN resistance management may be appropriate as

SCN populations are relatively sedentary with respect to field-to-field distribution and

movement. On the other hand, a tailored approach to managing the selection for virulent

populations of SCN on resistant soybean varieties is necessary. For other pathogens,

communities may be formed based on the distribution of these pathogens. For example,

white mold is most prevalent in northeastern Iowa while gray leaf spot is most common

in southern Iowa. By contrast, northern corn leaf blight is found throughout Iowa. Thus, disease communities need to consider environmental factors that increase the risk of

disease (e.g., soil type, precipitation and temperatures during the growing season, and

crop rotation).

Factors to be considered when areas within the state may benefit from more tailored,

community-based approaches, may include differences in farm size (and associated

issues of time management, movement of equipment, off-farm employment), rental vs.

owned land, use of custom applications/harvesting, cropping with or without animal

enterprises, soil types, tillage, weather, and other cultural practices that vary within parts

of the state and across years. IPM and RM strategies need to match those different

conditions and practices, and provide farmers and land owners flexibility to match their

situations.

5.5.2 Implementation drivers

One feature of the state plan might be a community-based farm organization that

facilitates the involvement and direction of key stakeholders including bankers, absentee

land owners, and land management firms. If someone is going to do business in the

community, they need to understand the sustainability goals that go along with being a

member of the community. Rather than focus on the farmer (or person who manages the

farm), the focus should be within the community. Perhaps a community-based group such

as bankers, land-management firms, and insurance agents could work together to

establish community-based sustainability goals, balancing short-term individual gains

with long-term community and environmental benefits. It needs to be understood by all

that the actions of any one farmer or collective group of farmers may impact the overall

community.

A pilot effort for a community-based approach or a phased-approach to statewide

implementation could be employed and address questions such as: At what scale does

influence happen? Who are the stakeholders and influencers? How do we address


contrasting pest management approaches when land is rented versus owned? Can the end

user influence how pests are managed?

There is a strong argument to use CCAs as one of the primary implementation drivers

(influencers) of this plan. There are 1,400 CCAs spread across the state. Other potential

implementation drivers are farm organizations, sales people, technology providers,

agronomists, product support personnel, commodity groups, and cooperatives. The

stakeholders and influencers extend to bankers, land managers, land owners, and

attorneys who draft rental agreements. As part of a community-based plan, sales

representatives from company technology providers in the state of Iowa could be charged

with upholding the sustainability principles created by the community. Technology

providers could build a reward system for their sales representatives who help their

customers build longer-term systems solutions for pest management and RM for their

farms. A potential conflict among technology providers may be anticipated when a RM

recommendation reduces the opportunity to sell their products.

5.5.3 Tools for community leaders

RM communities will emerge around the state as a result of the state RM plan and there

will be a need to provide tools for the community leaders so they can be successful in

their leadership role. There will also be a need for a source with the most up-to-date

information on RM practices. The plan will need to address how best to meet these needs.

5.6 Monitoring for results

Monitoring and scouting of pest populations will be a necessary feature of the state RM plan.

The RM plan should leverage existing policies for monitoring resistance and use outcomes to

determine if targets are being met.

Reporting of data and information should be voluntary and aimed at educating the community. If

the community is educated and can help farmers make appropriate decisions, rather than the

government or a particular company, there may be more trust and transparency within the

community.

Participants in the RM plan will need to have information about the presence of resistance. There

needs to be some type of reporting or pest survey to measure outcomes. Growers will need some

type of mechanism to share information if they have problems. Can a reward or benefit for

sharing information be provided or articulated by the state plan? If farmers can share information

to a trusted forum where they know they can get good advice or help, they may volunteer

potential pest management problems being experienced.


Can farmers be provided with a way to document that they are following an RM plan? Farmers

following RM plans will provide an example to others, and adherence to RM plans will likely be

important information for regulators. As a result, it is important to recognize and highlight

individuals in the community who are adopting good RM practices. Recognition of those

following RM plans could follow the example of a program such as Master Gardeners, where

people receive certification and provide some number of hours of outreach within the

community; or the Iowa Farm Environmental Leader Award, where individuals are recognized

as model practitioners of sound stewardship. Another example is the Soybean Rust First

Responders program, created by ISU/CALS

and the Iowa Soybean Association, which

prepared Iowa soybean farmers for the arrival

of soybean rust (Robertson and Tylka 2007).

Farmers and agricultural advisers who

participated in the training were recognized as

“First Responders.”

Types of monitoring to be implemented to inform a RM plan will differ for different types of

pests. Some aspects of monitoring are more logically incumbent upon a farmer or their crop

adviser and other types of monitoring are more appropriate for the pesticide registrant or other

parties. Registrants could support local scouting; support development of public domain

technology that reduces scouting input costs such as remote sensing, precision agriculture and

localized treatment options, grain sampling systems for weed seed identification; and perform

follow-up scouting in response to unexpected crop injury from a pest normally controlled.

More specific questions include when and what type of scouting is most effective. For example,

to manage weeds (resistant or otherwise), early is better. Scouting for weeds in crops in the V2-

V5 stages of development is optimal because a suite of weed management options (herbicides or

mechanical) is still in play.

To assess weed resistance, monitoring in August/September, prior to harvest, is the optimal time,

but likely only effective in soybean. Other pest complexes have different considerations.

Scouting for diseases, for example, is optimal in corn at R3-R5 and soybeans at R5-R6. In the

case of corn rootworm, scouting for unexpected injury could include an assessment of risk

factors; e.g., continuous corn with same Bt trait, late planting the previous year, lodging, high

adult population density, informal root evaluations, and water stress (Andow et al. 2015).

In general, routine monitoring is unlikely to detect pest resistance when it first arises because of

the scale over which a product is used and the necessarily limited number of samples that may be

collected and tested for resistance. Poor performance of a technology in the field is often the

most useful initial indicator of evolved resistance. However, care must be taken to rule out

alternative causes of poor field performance; e.g., disease samples could be sent to the

ISU/CALS Plant and Insect Diagnostic Clinic to assess pathogen sensitivity to a fungicide. Once

a resistance issue has become more widespread, either at a local or regional level, more routine

monitoring may be useful of characterizing the extent of resistance.

A key question is how does monitoring information develop into action and RM implementation.

The actions of individuals will be key components of an RM plan, but achieving the desired outcomes of these actions will require community-based approaches.


Additionally, once the plan is implemented it is possible for certain RM technologies that

confirmation testing could overwhelm current state and private testing facilities. The cost of

confirmation of pest resistance will undoubtedly increase with successful plan implementation

and must be considered.

5.7 Adaptive management approach

Monitoring for outputs (e.g., assessing the level of farmer and other sector participation in a RM

effort) and outcomes (e.g., assessing unexpected injury and/or resistance) to assess effectiveness

will help inform when modifications to practices are needed. Clearly a process for

communicating unexpected injury or resistance when detected will be needed. For example, the

zero tolerance program in Arkansas for Palmer amaranth provides an example of using

monitoring data to inform modification of practices (See

http://www.uaex.edu/publications/pdf/FSA2177.pdf). Importantly, this effort has waned due to

the retirement of the “champion.” Invasive weed and pest eradication programs are also

illustrative of community-based features for programs with coordinated, adaptive practices

undertaken by farmers and others in the crop production system.

5.8 Governance of a voluntary RM plan

While some resistance scenarios may lead to community-based, ‘local’ RM approaches, these

community-based efforts need to be nested within a state-wide effort that maximizes use of

cross-cutting knowledge and resources. Communities may need to be local in some cases, but

concepts, plans and efforts can and should be coordinated statewide to allow for consistency.

Consequently, IDALS would play a critical role within the state to ensure the voluntary RM

programs are performing in a manner consistent with the relevant federal pesticide registration

decisions. IDALS would also be the interface with EPA to ensure that the relevant federal

registration decisions (i.e., labels and conditions of registration) appropriately reference

Iowa’s state RM plan, providing Iowa farmers who voluntarily participate in the state RM

plan regulatory assurances.

EPA may be less likely to invoke mandatory RM requirements if viable state-based RM

programs are developed and implemented. Features of a state RM plan and practices required

through Federal labels and/or EPA’s conditions of registration would be similar, if not identical;

however, a state plan could have a greater degree of localized flexibility and adaptiveness than

could be attained through a national, regulation-based RM scheme. For a state RM plan to be

accepted by EPA as an alternative to a federal regulatory approach, the RM practices, monitoring

and adaptive approaches would likely need to result in outcomes (i.e., rates of resistance

development) consistent with FIFRA cost-benefit determinations in the specific registration

decisions.

6. RECOMMENDATIONS / CONSIDERATIONS FOR PLAN IMPLEMENTATION

Critical to implementation of a state RM plan is long-term engagement of the Iowa agricultural

community and allied industries. To accomplish this, the implementation framework needs to

http://www.uaex.edu/publications/pdf/FSA2177.pdf


consider an integrated approach for communications across specific sectors. Plan implementation

should build upon the science described in Section 4 of this paper and consider a tiered approach

for outlining and communicating different inputs, human behaviors, land-management strategies,

and outcomes for delaying resistance. The logic model below assumes an approach where plan

development and implementation is facilitated by IDALS and ISU/CALS to help ensure

communication and coordination across the agriculture industry, farmers and farm managers,

landowners and the general public.

Proposed Logic Model for Coordination across Sectors

Inputs Human behavior

(Activities)

Land Management

Industry Practice &

Crop Production

Pesticide Resistant

Population

Outcomes

Ag Industry– Retail Sales, Allied Supplier Organizations, Industrial and Private

Agronomists, Scientists, Academic Centers of Influence, Certified Crop Advisers,

Independent Crop Consultants

Development of

educational tools

and programs (IPM

upgrade – new

messaging in line

with current day

practices)

Central website for

providing access to

RM resources with

links to established

relevant resistance

websites

Use science-based

approach &

assessment for

public access

Socioeconomic

analysis –

demonstrate cost of

RM (short & long-

term costs)

Coordinate with &

support

‘Touchstone’ or

technical resource

Tiered

communications

approach – target

information flow at

the point of

University Extension-

to-Agribusiness

Identify

institutional/market

structures that can

lead to promotion of

practices that lead to

pest resistance

Survey of

recommended

practices:

-Adequacy of

University resources

to meet needs of

Agribusiness &

address questions in

field

-Awareness of RM

practices

-Interest in

implementing RM

practice

Increase the

inclusion of Mode of

Action on all

pesticide labels

Agribusiness may

not promote practices

that lead to pest

resistance

More fields are

scouted to identify

possible resistant

pests

Technologies will be

developed to identify

possible resistant

pests

Invest in

development of more

efficient & cost-

effective monitoring

techniques will be

adopted to confirm

resistant pests

Develop a site to

map baseline of

Minimize the

development and

spread of pest

resistance

Preserve crop

production

technologies for

farmers

Reduce the economic

impact of pest

resistance – trends

Measurement of plan

effectiveness

Consideration of

tangent geographic

zones relative to plan

implementation,

regular plan

upgrades, ability for

participation across

state lines, etc.


groups addressing

pest resistance (Take

Action, CropLife,

Weed Science

Society of America,

American

Phytopathological

Society,

Entomological

Society of America,

National Commodity

Groups, etc.)

Pursue alternative

funding sources for

incentivizing

farmers to adopt RM

practices (lease

agreements, product

line specific

program

coordination, Farm

Bill, other)

Reward for CCA –

IPM test

Specific links to

technology providers

to be defined

Support RM

workshops and

meetings (AAI

Showcase, ICM, ISA

Soybean Research

Conference, Crop

Advantage, Corn

Growers Crop Fairs,

Soybean Grower

Meetings) – identify

key network players

and “Champions”

Identify “Influencers”

within the existing

Agribusiness

community. Provide

means for

coordination across

Ag sectors and

association with state

RM plan

Compilation and

review of available

information

resistant pests,

possible forecasting

or grade of selection

pressures

Establish procedures

for admission of pest

resistance reporting

(USDA reports/sites,

private sources, and

other data. Need

consistency for IA

map- baseline)

Farmers, Farm Managers, and Land Owners --

Engage educational

outreach

Provide

existing/optional

RM practices

Scenario-based

socioeconomic

analysis to

demonstrate cost of

RM (short & long-

term costs)

Tiered

communications

approach – target

information flow at

the point of Farmer –

to-Agribusiness

Survey of

recommended

practices:

-Availability and

efficacy of RM tools

-Awareness of RM

practices

Land rent leases

include resistance

stewardship plans

Increase the number

of farmers using RM

practices

Minimize the

development and

spread of pest

resistance

Preserve technologies

available to farmers

Minimize the

economic impact of

pest resistance – field

results/examples


-Interest in

implementing RM

practice

-Communications

about RM practices

with Agribusiness

Identify Local and

Community

“Champions”

Provide means for

coordination across

Ag sectors and

association with state

RM plan

Maximize the

technology lifecycle

for farmers

General Public --

Campaign or

development of

messaging that

communicates

safety, healthy food,

and sustainability

Engagement of

youth curriculum:

FFA, 4-H, university

students, community

college students,

apprentice programs

Identify networks –

both farm/ag and

general public for

messaging

Monitor response and

adapt to address

concerns & questions

early on

Outreach &

Education

Develop safer,

healthy, sustainable,

and affordable food

Promote sustainable

food production

practices

Pest resistance issues are not new topics and much of the Iowa agricultural community is well

aware of the need for RM practices. The implementation framework for the state plan should

draw on the wealth of expertise from inside the state and beyond. Starting points may stem from

research findings, possibly a science-based assessment for Iowa, and/or build upon RM plans,

strategies/conceptual frameworks that are in place with other organizations or touchstones such

as:

Take Action

Weed science societies (Weed Science Society of America, North Central Weed Science

Society, Northeastern Weed Science Society, Southern Weed Science Society and

Western Society of Weed Science)

Plant Management Network

American Society of Agronomy

Certified Crop Adviser boards


Resistance Action Committees (insecticides: IRAC; herbicides: HRAC; fungicides:

FRAC)

Integrated Pest Information Platform for Extension and Education (iPIPE).

Opportunities to inform the logic model and build a strong implementation framework for Iowa

relies upon recognition of, and balance with, others working on RM practices.

Strong leadership in the agricultural community is needed from within each sector identified in

the logic model. The implementation framework should facilitate recognition of individuals, and

support leaders or ‘champions’ that emerge in the area of RM. It is these individuals who can

operate on both local and community levels, and who are essential to achieving long-term goals

of an RM plan.

In addition, real-time feedback regarding agricultural communities’ and the general public’s

reactions to socioeconomic analyses contain great value in understanding why certain RM

practices may be adopted and why other practices may not be so widely adopted.

Additional considerations of the implementation framework might focus on coordination with

entities that could serve as “influencers,” a role that can support, in some capacity, efforts put

forth by champions at the local and community levels. Several Iowa-based organizations are

already engaged in the topic of RM, including those represented at the January 2015.

Finally, the implementation framework should take into consideration existing organizations,

current roles and networks within the Iowa community, resource/time allocation, and

opportunities for future funding – all of which, may assist in providing opportunities for future

leadership and further facilitation and support of the plan framework.


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http://dx.doi.org/10.1093/jee/tov238.

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http://www.soc.iastate.edu/extension/ifrlp/PDF/PM3070.pdf.

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APPENDICES

Appendix A. Task Force Contributors to the Conceptual Framework Document

Ed Anderson, Iowa Soybean Association

J. Gordon Arbuckle, Jr., Iowa State University, College of Agriculture and Life

Sciences (ISU/CALS)

Amy Asmus, Agribusiness Association of Iowa

Steven Bradbury, ISU/CALS

David Ertl, Iowa Corn Growers Association

Jim Gulliford, Soil and Water Conservation Society

Kim Heckert, Iowa Institute for Cooperatives

Aaron Gassmann, ISU/CALS

Ben Gleason, Iowa Corn Growers Association

Ed Kordick, Iowa Farm Bureau Federation

John Miranowski, ISU/CALS

Daren Mueller, ISU/CALS

Micheal Owen, ISU/CALS

Gretchen Paluch, Iowa Department of Agriculture and Land Stewardship, Pesticide

Bureau

Clint Piltcher, Agriculture Biotechnology Stewardship Technical Committee

Larry Pohlman, American Society of Farm Managers and Appraisers, Iowa Chapter

Peter Porpiglia, Resistance Action Committees

Alison Robertson, ISU/CALS

Greg Tylka, ISU/CALS


Appendix B. January 30, 2015, Resistance Management Meeting Recommendations for a

State Resistance Management Plan

(see Appendix B in http://www.ipm.iastate.edu/content/pesticide-resistance-workshop-2015 )

Develop a state-wide resistance management strategy

o State ownership to minimizing regulatory intervention by EPA

o Coordination should be at state level (perhaps modeled like the Iowa Nutrient Reduction

Strategy); realize one size does not fit all; i.e., resistance management plans could be

different across the state

o Requires strong leadership and coordination within and across organizations

o Not bottom up or top down approach - it needs to work for farmers and be sustainable

and cohesive

o Broad participation

o Coordinated approach with industry

o Defined roles for all sectors in agriculture

o Include: weeds, insects, pathogens, economics, society, community, culture, geography,

climate, cultural and management practices

Other examples may be instructive to forming a state resistance management

program e.g., boll weevil (but pest specific), Australia glyphosate resistance

(but different socio-economic/regulatory environment); citrus greening in

Florida

o Care in public communication of the plan; need to establish progress first

Potential tactical aspects of developing and implementing a state resistance

management strategy

o Socio-economic dimensions of problem and solution; understand and evaluate

incentives – economic, personal and social

o Appeal for simple solutions and need to address ‘old school’ versus new generation pest

management approaches – both will likely play a role

o Broaden definition of ‘community’ to include precision agriculture and financial

institutions

o Role of check-off or other mechanisms to provide funding

o Delivery of information and tools will be a key aspect

Awareness and opportunity to take action

o Near term- Need to provide unified message on resistance management for the state

o How to ensure resistant management is a priority on farm for all organizations?

o Education across groups; key role for ISU/CALS extension to be a hub of information to

support farmers and their advisers

Education/Outreach could include:

o CCA education

o Pesticide Certification Education

o Other audiences

Critical for meeting participants to take messages from the meeting to constituent

groups now

http://www.ipm.iastate.edu/content/pesticide-resistance-workshop-2015

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